Ackman, who has teamed up with Canadian pharmaceutical company Valeant to launch a $45.6 billion takeover of Botox maker Allergan, warned drugmakers Tuesday that he plans to go on a little buying spree.

“This is not the last deal we’re going to do,” he said. “We’re already talking about the next deal we’re going to do with Valeant.”

“There are $10 trillion worth of targets,” said Ackman, referring to the combined market cap of the pharmaceutical industry. “I call this the shopping list.”

Ackman has invested about $3.2 billion in Allergan, most of it done in options during the past six days in order to avoid regulatory scrutiny while he amassed his stake.

The drugmaker now accounts for 30 percent of his more than $13 billion Pershing Square hedge fund firm, which gained about $900 million overnight as Allergan shares soared 15 percent, closing at $163.50 Tuesday.

As a big shareholder, Ackman plans to wear his activist hat to convince Allergan shareholders, and management, to hook up with Valeant.

“We’re going to work very hard to make this transaction happen,” he said, hinting that if it isn’t approved, “We’ll do what we have to do. We’d be really unhappy.”

In a statement, Allergan said it would review the Valeant proposal.

Ackman was introduced to Valeant CEO J. Mike Pearson earlier this year, and by early February they had decided on a merger target.

Pearson acknowledged that Allergan’s Botox drug, which is injected in facial muscles to get rid of wrinkles, is the “driver” of the deal. “If something happened to Botox, this would be a bad deal,” he said.

Separately, Ackman, who placed a $1 billion bet against Herbalife, acknowledged on Tuesday he agreed to pay a former Herbalife exec up to $3.6 million for becoming a whistle blower.

Ackman agreed to pay Giovanni Bohorquez in case he lost the job he took after leaving Herbalife. So far, he has collected $80,000 under the arrangement, according to ABC News.

Ackman said he struck the secret deal after Bohorquez balked at providing information to government investigators about alleged problems at an Herbalife manufacturing plant.

“It was the right thing to do,” Ackman told ABC News, which said Bohorquez initially denied he was being paid anything by Ackman.